Intelligent Power Today Magazine

How to reduce electrical-related deaths and injuries to zero

BY JENIFER ROBERTSON, Electrical Safety Authority

Consider this scenario: An electrician is modifying an electrical circuit in a ceiling space at an educational institute. To perform the task, he de-energizes his specific circuit, but leaves the others in the same junction box energized.

While making the wiring modifications, the electrician makes incidental contact with a 347-volt, energized conductor with his right thumb and baby finger. He receives a shock.

Does this sound like a rarity? Well, it is not. In fact, this is a real-life incident that happened in Ontario—and it...

Absence of voltage testing is a vital step in the process of verifying and establishing a de-energized state of any electrical system. As detailed in NFPA 70E clause 4.2.5., there is a specific and approved approach to establishing an electrical safe work condition with the following steps:

• determine all possible source of electrical supply
• interrupt the load current, open the disconnecting device for each possible source
• verify where possible that all blades of the disconnecting devices are open
• release or block any stored energy
• apply lockout device in accordance with documented and established work procedures
• using an adequately rated portable...